KR102122495B1 - Apparatus and method for providing streaming contents using representation - Google Patents

Abstract

A method and apparatus for an adaptive HTTP streaming service that uses metadata for media content is disclosed. Media content consists of a series of one or more cycles. Each cycle can include one or more representations. Metadata includes information describing relationships between representations, and information for terminals having different display bit depths.

Description

Device and method for providing streaming content using representation{APPARATUS AND METHOD FOR PROVIDING STREAMING CONTENTS USING REPRESENTATION}

The technical field of the present invention relates to a technology for providing streaming content, and more particularly, to an apparatus and method for providing media content using a representation of media content.

Streaming is one of methods for transmitting and playing multimedia content such as sound and video. The client can play the content while receiving the content through streaming.

The adaptive streaming service means providing a streaming service through a communication method composed of a client request and a server response to the request.

The client can request a media sequence suitable for his environment (eg, his transport channel) through an adaptive streaming service, and the server can select a media sequence that meets the client's request from among various quality media sequences he has Can provide.

The adaptive streaming service can be provided based on various protocols. The HTTP adaptive streaming service means an adaptive streaming service provided based on the HTTP protocol. The client of the HTTP adaptive streaming service can receive content from the server using the HTTP protocol, and send a request related to the streaming service to the server.

One embodiment of the present invention can provide an apparatus and method for playing media content using representations including accessibility information.

One embodiment of the present invention can provide an apparatus and method for playing media content using information describing a relationship between representations of media content.

One embodiment of the present invention can provide an apparatus and method for playing media content using information of different representations for terminals having different display bit depths.

According to one side, receiving metadata of media content including one or more periods, accessing segments of the media based on information provided by the metadata, and the media content included in the segments Decoding and rendering the data of each cycle, each cycle comprising one or more representations of the media, each representation providing information to assist persons with disabilities who are having difficulty in perceiving the media content. A media providing method is provided.

The media component of the representation is augmented to cope with the problem of a person with a disability, and the augmentation is at least one of an increase in contrast and a correction in color.

Wherein the information indicates the intended use of the representation, and the intended use is one or more of sign language, subtitles, captions and descriptions.

The information may include an attribute that provides a reference to an external MPEG-21 Digital Item Adaptation (DIA).

According to another aspect, receiving metadata of media content including one or more periods, accessing segments of the media based on information provided by the metadata, and the media included in the segments Decoding and rendering data of the content, each period comprising one or more representations of the media, and the metadata including attributes describing the relationship between the one or more representations A method of providing may be provided.

The first representation among the one or more representations may include an attribute indicating a list of representations of some of the one or more representations, and the first representation may include a representation of the part It can be used with any of the presentations.

The first representation may be a representation for audio description.

Each of the representations may be a representation of a video component.

The first representation of the one or more representations may include an attribute indicating a list of some of the representations of the one or more representations.

Representation of one of the partial representations may be used in place of the first representation.

According to another aspect, receiving metadata of a media content including one or more periods, accessing segments of the media based on information provided by the metadata, and the contained within the segments Decoding and rendering data of the media content, each period comprising one or more representations of the media, each representation selecting a different representation for terminals with different display bit depths A method of providing media may be provided, including the bit depth attribute used for the purpose.

The bit depth attribute may indicate the number of bits for representing a luma/chroma sample of visual content.

According to another aspect, receiving metadata of media content including one or more periods, receiving segments of the media based on information provided by the metadata, and data of the media included in the segments And a media engine that receives the data of the media from the access engine and outputs the media, each cycle including one or more representations of the media, and each representation is the media. A terminal may be provided, which includes information for supporting people with disabilities who are having difficulty in perceiving content.

According to another aspect, receiving metadata of media content including one or more periods, receiving segments of the media based on information provided by the metadata, and data of the media included in the segments And a media engine that receives the data of the media from the access engine and outputs the media, wherein each cycle includes one or more representations of the media, and the metadata is the one or more. A terminal may be provided, which includes attributes describing the relationship between representations.

According to another aspect, receiving metadata of media content including one or more periods, receiving segments of the media based on information provided by the metadata, and data of the media included in the segments And a media engine that receives the data of the media from the access engine and outputs the media, wherein each cycle includes one or more representations of the media, and each representation is a different display. A terminal may be provided, including bit depth attributes used to select different representations for terminals with bit depths.

The method and apparatus according to an embodiment of the present invention may play media content using representations including accessibility information.

A method and apparatus according to an embodiment of the present invention may play media content using information describing a relationship between representations of media content.

The method and apparatus according to an embodiment of the present invention can play media content using information of different representations for terminals having different display bit depths.

1 shows a high-level data model of DASH.
2 is a signal flow diagram of a content processing method according to an embodiment of the present invention.
3 illustrates categories of signaling information according to an example of the present invention.
FIG. 4 shows the level of content division layer and signaling information according to an example of the present invention.
5 is a structural diagram of a terminal according to an embodiment of the present invention.

The entire document "Dynamic adaptive streaming over HTTP (DASH)-Part 1: Media presentation description and segment format" of ISO/IEC DIS 23009-1 published on August 30, 2011 can be cited as a reference in this application. , Reference may be made to the following examples.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited or limited by the embodiments. The same reference numerals in each drawing denote the same members.

In the following, "specify" may be used in the same sense as "represents" or "means." The terms "Uniform Resource Locator (URL)" and "Uniform Resource Identifier (URI)" are used interchangeably and may be interchanged.

When an index of a specific element is 1 to N or 0 to N, the element may be one or more. N may represent an integer of 0 or more.

In the following, an example of terms used in the embodiments is described.

-Dynamic Adaptive Streaming over HTTP (DASH) enables 1) delivery of media content from a standard HTTP server to an HTTP client, and 2) by standard HTTP caches. It is possible to specify formats that enable caching of content. The format may be an XML format or a binary format.

-The media content may be a media content period of Honey or a contiguous sequence of media content periods. In the following, media content, media and content may be used interchangeably with each other. The media content can be a collection of media content components having a common timeline, such as video, audio and subtitles. In addition, media components have relations as to how the media components will be presented (eg, individually, jointly, or mutually exclusive) as a program or movie. The media content may be content on demand or live content.

Content may be divided into one or more intervals. That is, the content may include one or more intervals. Hereinafter, intervals and periods may be used in the same sense. In particular, the cycle may be a term used in 3GPP (Generation Partnership Project) adaptive HTTP streaming. The period can be an interval of media presentation. The continuous sequence of all periods can constitute a media presentation.

One or more intervals may be a basic unit. One or more intervals may be described by signaling metadata. That is, the metadata may describe each of one or more intervals. The metadata may be MPD to be described later.

-The media content component may be a continuous component of media content having an assigned media component type. Media content components can be encoded into individual media streams. Media components are, for example, audio, video or timed text with specific attributes, such as bandwidth, language or resolution. It may be an encoded version of individual media types.

-The media stream can be an encoded version of the media content component.

-The media component type may be a single type of media content such as audio, video, or text.

-The media presentation may be a collection of data that establishes a bound or unbound presentation of media content. The media presenter may be a collection of data accessible to DASH clients to provide streaming services to users. MPD can be described by MPD. The media presentation may be a structured collection of data accessible to DASH clients to provide streaming services to users.

-Media Presentation Description (MPD) may be a formalized description of a media presentation for providing a streaming service. The MPD may be a document containing metadata required by the client of DASH to construct a suitable HTTP-URL for accessing the segment and provide streaming service to the user. The media presentation may include possible updates of the MPD, and may be described by at least one MPD.

The MPD may be a document that includes metadata required by the DASH client to 1) access segments, and 2) construct HTTP-URLs suitable to provide streaming services to the user. HTTP-URLs can be absolute or relative. The MPD can be an XML-document.

MPD may define a format for informing resource identifiers for a segment. The MPD can provide context for identified resources within the media presentation. Resource identifiers may be HTTP-URL. URLs can be limited by the byte range attribute.

-The period may be an interval of media presentation. Continuing sequences of all cycles can constitute a media presentation. That is, the media presentation may include one or more periods. Or, the media presentation may consist of a sequence of one or more periods.

-Representation may be a collection and encapsulation of one or more media streams in a delivery format, and may be associated with descriptive metadata. The representation can be a structured collection of one or more media components within a period. That is, the representation may be one of alternative choices of a complete set or subset of media content components that make up the media content for a defined period. The representation may include one or more media streams.

The representation can start at the start of the cycle (ie, the cycle that includes it), and can continue to the end of the cycle.

Representation is an alternative to media content or a subset of media content, with different encoding choices, such as bitrate, resolution, language, and codec. alternative) may be one of the choices.

The MPD (or MPD element) may provide descriptive information that enables the client to select one or more representations.

In the following, representations and media representations may be used in the same sense.

There may be two or more sets of segments corresponding to one interval, and the set may be referred to as a representation or alternative.

-A segment may be the least accessible unit in an MPD with a defined format. In the following, segments and media segments may be used in the same sense.

Each interval can be divided into segments. In the following, segments and fragments can be used in the same sense. Segment may be a term of 3GPP (Generation Partnership Project) adaptive HTTP streaming.

A segment is an object of a response to an HTTP/1.1 GET request to HTTP-URL (or GET request to a portion indicated by a byte range), as defined in RFC 2616, for example. entity) may mean a body.

The terminal may play the media content using the received bytes (ie, segment).

-A sub-segment may mean the smallest unit in segments that can be indexed by a segment index at the segment level.

-The sub-representation may be part of the representation described in the MPD staged in the entire cycle.

-A random access point (RAP) is a specific location within a media segment. The RAP is identified as a location that can continue playback from the location of the RAP using only the information contained within the media segment.

Dynamic adaptive streaming over HTTP (DASH) can provide a media-streaming model for the delivery of media content. The client can exclusively control the session of the delivery. The client can request data from a standard web server that does not have DASH-specific functions using the HTTP protocol. Thus, the DASH standard can be focused on the data format used to provide DASH media presentations.

A collection of encoded and deliverable versions of media content and appropriate descriptions of these versions can form a media presentation. Media content may consist of one or more media content cycles that continue over time. Each media content cycle may consist of one or more media content components. For example, audio components and video components in various languages may be examples of one or more media content components. Each media content component may be assigned a media content component type. An example of a media content component type may be audio or video.

Each media content component can have one or more encoded versions. The encoded version of the media content component may be referred to as a media stream. Each media stream can inherit the properties of media content, media content cycle or media content used for encoding of the media stream. In addition, the media stream can be assigned attributes of the encoding process, such as sub-sampling, codec parameters, encoding bitrate, and the like. Thus, metadata can be changed according to static or dynamic selection of media content components and media streams.

1 shows a high-level data model of DASH.

DASH may be based on a hierarchical data model as shown in FIG. 1.

DASH media presentations can be described by MPD documents. MPD can describe a sequence of periods over time. The sequence of cycles can make a media presentation. The period can generally indicate the period of the media content while a consistent set of encoded versions of the media content is available. That is, bitrates, languages, captions, and subtitles may not be changed during one cycle.

The period may include one or more adaptation sets. The adaptation set may represent a set of replaceable encoded versions of one or more media content components. For example, there may be one adaptation set for the main video component, and there may be one separate adaptation set for the main audio component. If there are other available materials, such as captions and audio descriptions, for example, the above other available materials may have separate sets of adaptations.

The adaptation set may include one or more representations. The representation can describe a deliverable encoded version of one or more media components. The representation may include one or more media streams. Any single representation in the adaptation set may be sufficient to render the media content components involved. In general, a client can switch from one representation to another to adapt to network conditions or other factors within one cycle. The client may ignore representations that rely on codec or other rendering techniques that the client itself does not support or that is not suitable for other reasons.

Within the representation, content can be divided into segments over time. That is, the representation may include one or more segments. A segment can be a basic unit of data, as represented in the MPD. The URL of each segment can be provided. Providing a segment's URL can mean that the segment is the largest unit of data that can be retrieved by a single HTTP request. Meanwhile, the MPD may include a byte range of the URL along with the URL. Thus, a segment may be included within the byte range of other larger resources.

In the following, the relationship between the components of the data model described above is explained.

-MPD may include a chain of one or more periods.

-Each period may include one or more adaptation sets. If the adaptation includes one or more media content components, each media content component can be defined individually.

-Each adaptation set may include one or more representations.

-Each representation may include one or more sub-representations.

-Each representation may contain one or more segments.

-Segments may include media data and/or metadata for accessing, decoding and presenting the media content contained therein.

-The adaptation set, representation and sub-representation can share common attributes and elements.

-Each segment may include one or more subsegments.

The MPD document representing the MPD may include MPD elements.

Table 1 below may represent an XML schema of MPD according to an example.

<?xml version="1.0"encoding="UTF-8"?>
<xs:schema targetNamespace="urn:mpeg:DASH:schema:MPD:2011"
attributeFormDefault="unqualified"
elementFormDefault="qualified"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:xlink="http://www.w3.org/1999/xlink"
xmlns="urn:mpeg:DASH:schema:MPD:2011">

<xs:import namespace="http://www.w3.org/1999/xlink"
schemaLocation="http://www.w3.org/1999/xlink.xsd"/>

<xs:annotation>
<xs:appinfo>Media Presentation Description</xs:appinfo>
<xs:documentation xml:lang="en">
This Schema defines the Media Presentation Description for MPEG-DASH.
</xs:documentation>
</xs:annotation>

<!-- MPD: main element -->
<xs:element name="MPD"type="MPDtype"/>

...

</xs:schema>

Table 1 may indicate an initial part of the MPD's XML schema. The initial part of the above may include namespaces and other definitions.

A mechanism for referencing remote elements from a local MPD can be defined. A subset of W3C XLIM simple links with 1) limited syntax and semantics, and 2) processing models can be defined.

The XLINK attributes used as part of ISO/IEC 23009 may be as follows.

-The xlink:type attribute can define the type of W3C XLINK used.

-The xlink:href attribute can identify a remote element using a URI, as defined in IETF RFC 3986.

-The xlink:show attribute can define the desired behavior of a remote element once dereferenced in the MPD, as defined in W3C XLINK.

-The xlink:actuate attribute can define the desired timing at which the remote object is referenced within the MPD, as defined in W3C XLINK.

Table 2 below may represent an XML schema of XLINK according to an example.

<?xml version='1.0'encoding='UTF-8'?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
targetNamespace="http://www.w3.org/1999/xlink"
xmlns:xlink="http://www.w3.org/1999/xlink">

<xs:attribute name="type"type="xs:token"fixed="simple"/>

<xs:attribute name="href"type="xlink:hrefType"/>

<xs:simpleType name="hrefType">
<xs:restriction base="xs:anyURI"/>
</xs:simpleType>

<xs:attribute name="show"type="xs:token"fixed="embed"/>

<xs:attribute name="actuate"type="xlink:actuateType"default="onRequest"/>

<xs:simpleType name="actuateType">
<xs:restriction base="xs:token">
<xs:enumeration value="onLoad"/>
<xs:enumeration value="onRequest"/>
</xs:restriction>
</xs:simpleType>
</xs:schema>

In the above schema, the namespace, name, type and default value of each element or each attribute can be described. Also, the hierarchical relationship between elements and attributes can be described.

The rules for handling URI references in the xlink:href attribute may be as follows.

-URI references to remote elements that cannot be resolved can be treated as invalid references and invalidate the MPD.

-A URI reference to a remote element that is an invalid target for a given reference can be treated as an invalid reference and render the MPD invalid.

-URI references that directly or indirectly refer to themselves may be treated as invalid circular references, and may render the MPD invalid.

-Any reference to a remote element can be HTTP-URL.

-If the URI reference is relative, a reference resolution may be applied.

The semantics of the MPD element are described below.

1) The MPD element may have the following attributes.

-The id attribute may specify the identifier of the media presentation. The id attribute may be a unique identifier within the scope of the published MIDI presentation.

-The type attribute can specify whether the MPD can be updated.

-The mediaPresentationDuration attribute may specify the duration of the entire media presentation. If the mediaPresentationDuration attribute is absent, the duration of the media presentation may be unknown.

-The maxSegmentDuration attribute may specify the maximum duration of any segment in any representation in the media presentation.

2) The MPD element may have the following elements.

-The ProgramInformation element may have an index of 0 to N, and may specify descriptive information about the program. Being able to have an index of N can mean that the number of instances of an element can be unlimited. Being able to have an index of 0 means that the element is optional. Being able to have an index of at least 1 can indicate that the element is mandatory. That is, the range of the index may indicate the number of occurrences (occurrence) or cardinality (cardinality).

-The BaseURL element may have an index of 0 to N, and may specify a base URL that can be used for reference resolution and alternative URL selection.

-The Location element may have an index of 0 to N, and may specify the location where the MPD is available.

-Period element, may have an index of 1 to N, may specify the information of the period.

-The Metrics element may have an index of 0 to N, and may specify DASH metrics.

Table 3 below may represent XML syntax of an MPD element according to an example.

<!-- MPD Type -->
<xs:complexType name="MPDtype">
<xs:sequence>
<xs:element name="ProgramInformation"type="ProgramInformationType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="BaseURL"type="BaseURLType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Location"type="xs:anyURI"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Period"type="PeriodType"maxOccurs="unbounded"/>
<xs:element name="Metrics"type="MetricsType"minOccurs="0"maxOccurs="unbounded"/>
<xs:any namespace="##other"processContents="lax"minOccurs="0"maxOccurs="unbounded"/>
</xs:sequence>
<xs:attribute name="id"type="xs:string"/>
<xs:attribute name="profiles"type="xs:string"/>
<xs:attribute name="type"type="PresentationType"default="static"/>
<xs:attribute name="availabilityStartTime"type="xs:dateTime"/>
<xs:attribute name="availabilityEndTime"type="xs:dateTime"/>
<xs:attribute name="mediaPresentationDuration"type="xs:duration"/>
<xs:attribute name="minimumUpdatePeriod"type="xs:duration"/>
<xs:attribute name="minBufferTime"type="xs:duration"use="required"/>
<xs:attribute name="timeShiftBufferDepth"type="xs:duration"/>
<xs:attribute name="suggestedPresentationDelay"type="xs:duration"/>
<xs:attribute name="maxSegmentDuration"type="xs:duration"/>
<xs:attribute name="maxSubsegmentDuration"type="xs:duration"/>
<xs:anyAttribute namespace="##other"processContents="lax"/>
</xs:complexType>

<!-- Presentation Type enumeration -->
<xs:simpleType name="PresentationType">
<xs:restriction base="xs:string">
<xs:enumeration value="static"/>
<xs:enumeration value="dynamic"/>
</xs:restriction>
</xs:simpleType>

The media presentation can include one or more periods. The period can be defined by the Period element in the MPD element.

The period may be divided into a regular period and an early available period. The PeriodStart time of a regular period may be defined as follows.

-If there is a start attribute in the period element, the period may be a regular period, and the PeriodStart time may be the same as the value of the start attribute.

-When the start attribute is absent in the periodic element, and the previous Period element includes the duration attribute, the period may be a regular period. The start time of the period PeriodStart may be the sum of the start time of the previous period and the value of the duration attribute of the previous period.

-If 1) the start attribute is absent, 2) the Period element is the first in the MPD, and 3) the type attribute of the MPD is'static', the PeriodStart time may be 0.

-1) If the start attribute is absent, 2) If the previous Period element does not contain the duration attribute, or if the Period element is the first in the MPD, and 3) the type attribute of the MPD is'dynamic', then the period Can be an early availability cycle.

The semantics of the Period element are described below.

1) The Period element may have the following attributes.

-The xlink:href attribute can specify a reference to an external Period element.

-The xlink:actuate attribute can specify processing instructions. The value of the link:actuate attribute may be "onload" or "onRequest".

-The id attribute can specify the identifier of the cycle. The id attribute may be a unique identifier within the scope of the MIDI presentation.

-The start attribute can specify the PeriodStart time of the period. The PeriodStart time can be used as an anchor to determine the MPD start time of each media segment, and can be used to determine the presentation time of each access unit in the media presentation timeline.

-The duration attribute can specify the duration of the cycle to determine the PeriodStart time of the next cycle.

2) The Period element may have the following elements.

-The BaseURL element may have an index of 0 to N, and may be used for reference solutions and alternative URL selection.

-The AdaptationSet element may have an index of 1 to N, and may specify information of the adaptation set.

-The Subset element may have an index of 0 to N, and may specify a subset.

Table 4 below may represent the XML syntax of the Period element according to an example.

<!-- Period -->
<xs:complexType name="PeriodType">
<xs:sequence>
<xs:element name="BaseURL"type="BaseURLType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="SegmentBase"type="SegmentBaseType"minOccurs="0"/>
<xs:element name="SegmentList"type="SegmentListType"minOccurs="0"/>
<xs:element name="SegmentTemplate"type="SegmentTemplateType"minOccurs="0"/>
<xs:element name="AdaptationSet"type="AdaptationSetType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Subset"type="SubsetType"minOccurs="0"maxOccurs="unbounded"/>
<xs:any namespace="##other"processContents="lax"minOccurs="0"maxOccurs="unbounded"/>
</xs:sequence>
<xs:attribute ref="xlink:href"/>
<xs:attribute ref="xlink:actuate"default="onRequest"/>
<xs:attribute name="id"type="xs:string"/>
<xs:attribute name="start"type="xs:duration"/>
<xs:attribute name="duration"type="xs:duration"/>
<xs:attribute name="bitstreamSwitching"type="xs:boolean"default="false"/>
<xs:anyAttribute namespace="##other"processContents="lax"/>
</xs:complexType>

Each cycle may include one or more adaptation sets. The adaptation set may be described by the AdaptationSet element included in the Period element.

The adaptation set can include alternative encodings of one or more media components. Each alternative encoding can be included in the representation. One or more representations included in one adaptation set may represent the same media content component, and may include one or more media streams that are perceptually considered the same.

Representations of one arcing can be arranged in an adaptation set according to media content component properties staged in one or more of the above representations. The media content component properties are: 1) the language described by the lang attribute, 2) the media content type described by the contentType attribute, 3) the picture aspect ratio described by the par attribute, and 4) the Role element. It may include a role property described by, 5) an accessibility property described by an Accessibility element, 6) a viewpoint property described by a ViewPoint element, and 6) a rating property described by a Rating element.

The AdaptationSet element may include basic values of elements and attributes related to one or more representations included in the adaptation set. A list of possible present elements and attributes common to the AdaptationSet element and the Representation element is described below.

The Adaptation element may support description of a range of bandwidth attributes, width attributes, height attributes, and framerate attributes associated with one or more representations included in the adaptation set. The above description may provide a summary of all values for all one or more representations included in the adaptation set. One or more representations included in the adaptation set may not have a value outside the range defined within the adaptation set.

The adaptation set can be classified into groups by using the group attribute.

The semantics of the AdaptationSet element are described below.

1) The AdaptationSet element can have the following attributes.

-The xlink:href attribute can specify a reference to an external AdaptationSet element.

-The xlink:actuate attribute can specify processing instructions. The value of the link:actuate attribute may be "onload" or "onRequest".

-The id attribute may specify the identifier of the adaptation set within the scope of the cycle. The id attribute may be a unique identifier within a range including the period. The id attribute may be absent within the remote element.

-The group attribute may be an identifier for a group, unique within the scope of the period.

-The lang attribute can declare the language code(s) of the adaptation set. Syntax and semantics according to IETF RFC 5646 can be used.

-The contentType attribute may specify the media content component type of the adaptation set. The value of "type" which is the top-level content-type may be defined in RFC1521.

-The par attribute can specify the ratio of the photo length. The par attribute may include 2 integers. When the par attribute is present, width and height attributes of representations may also be present.

-The minBandWidth attribute may specify the minimum bandwidth attribute value of all representations in the adaptation set.

-The maxBandWidth attribute may specify the maximum bandwidth attribute value of all representations in the adaptation set.

-The minWidth attribute may specify the minimum width attribute value of all representations in the adaptation set.

-The maxWidth attribute may specify the maximum width attribute value of all representations in the adaptation set.

-The minHeight attribute may specify the minimum height attribute value of all representations in the adaptation set.

The maxHeight attribute may specify the maximum height attribute value of all representations in the adaptation set.

-The minFrameRate attribute may specify the minimum frameRate attribute value of all representations in the adaptation set.

-The maxFrameRate attribute may specify the maximum frameRate attribute value of all representations in the adaptation set.

2) The AdaptationSet element may have the following elements.

-The Accessbility element may have an index of 0 to N, and may specify information about an accessibility scheme.

-The Role element may have an index of 0 to N, and may specify information about a roll annotation scheme.

-The rating element may have an index of 0 to N, and may specify information on a rating scheme.

-The Viewpoint element may have an index of 0 to N, and may specify information about the viewpoint annotation scheme.

-The ContentComponent element may have an index of 0 to N, and may specify properties of a media content component included in the adaptation set.

-The BaseURL element may have an index of 0 to N, and may be used for reference solutions and alternative URL selection.

-The Representation element may have an index of 0 to N, and may specify a representation. There may be at least one representation element within each adaptation set. The Representation element may be part of a remote element.

Table 5 below may represent XML syntax of the AdaptationSet element according to an example.

<!-- Adaptation Set -->
<xs:complexType name="AdaptationSetType">
<xs:complexContent>
<xs:extension base="RepresentationBaseType">
<xs:sequence>
<xs:element name="Accessibility"type="DescriptorType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Role"type="DescriptorType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Rating"type="DescriptorType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Viewpoint"type="DescriptorType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="ContentComponent"type="ContentComponentType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="BaseURL"type="BaseURLType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="SegmentBase"type="SegmentBaseType"minOccurs="0"/>
<xs:element name="SegmentList"type="SegmentListType"minOccurs="0"/>
<xs:element name="SegmentTemplate"type="SegmentTemplateType"minOccurs="0"/>
<xs:element name="Representation"type="RepresentationType"minOccurs="0"maxOccurs="unbounded"/>
</xs:sequence>
<xs:attribute ref="xlink:href"/>
<xs:attribute ref="xlink:actuate"default="onRequest"/>
<xs:attribute name="id"type="xs:unsignedInt"/>
<xs:attribute name="group"type="xs:unsignedInt"/>
<xs:attribute name="lang"type="xs:language"/>
<xs:attribute name="contentType"type="xs:string"/>
<xs:attribute name="par"type="xs:string"/>
<xs:attribute name="minBandwidth"type="xs:unsignedInt"/>
<xs:attribute name="maxBandwidth"type="xs:unsignedInt"/>
<xs:attribute name="minWidth"type="xs:unsignedInt"/>
<xs:attribute name="maxWidth"type="xs:unsignedInt"/>
<xs:attribute name="minHeight"type="xs:unsignedInt"/>
<xs:attribute name="maxHeight"type="xs:unsignedInt"/>
<xs:attribute name="minFrameRate"type="xs:string"/>
<xs:attribute name="maxFrameRate"type="xs:string"/>
<xs:attribute name="segmentAlignment"type="ConditionalUintType"default="false"/>
<xs:attribute name="subsegmentAlignment"type="ConditionalUintType"default="false"/>
<xs:attribute name="subsegmentStartsWithSAP"type="SAPType"default="0"/>
<xs:attribute name="bitstreamSwitching"type="xs:boolean"/>
</xs:extension>
</xs:complexContent>
</xs:complexType>

<!-- Conditional Unsigned Integer (unsignedInt or boolean) -->
<xs:simpleType name="ConditionalUintType">
<xs:union memberTypes="xs:unsignedInt xs:boolean"/>
</xs:simpleType>

The adaptation set may include one or more media content components. The properties of each media content component can be described by the ContentComponet element, and if there is one media content component in the adaptation set, it can be directly described by the AdaptationSet element.

The semantics of the ContentComponent element are described below.

1) ContentComponent element can have the following properties.

-The id attribute may specify the identifier of the media component. The id attribute can be unique within the scope of the adaptation set.

-The lang attribute can declare the language code(s) of the media content component. Syntax and semantics according to IETF RFC 5646 can be used.

-The contentType attribute may specify the type of media content component. The value of "type" which is the top-level content-type may be defined in RFC1521.

-The par attribute can specify the ratio of the photo length. The par attribute may include 2 integers. When the par attribute is present, width and height attributes of representations may also be present.

2) The ContentComponent element may have the following elements.

-The Accessbility element may have an index of 0 to N, and may specify information about an accessibility scheme.

-The Role element may have an index of 0 to N, and may specify information about a roll annotation scheme.

-The rating element may have an index of 0 to N, and may specify information on a ration scheme.

-The Viewpoint element may have an index of 0 to N, and may specify information about the viewpoint annotation scheme.

Table 6 below may represent XML syntax of a ContentComponent element according to an example.

<!-- Content Component -->
<xs:complexType name="ContentComponentType">
<xs:sequence>
<xs:element name="Accessibility"type="DescriptorType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Role"type="DescriptorType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Rating"type="DescriptorType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Viewpoint"type="DescriptorType"minOccurs="0"maxOccurs="unbounded"/>
<xs:any namespace="##other"processContents="lax"minOccurs="0"maxOccurs="unbounded"/>
</xs:sequence>
<xs:attribute name="id"type="xs:unsignedInt"/>
<xs:attribute name="lang"type="xs:language"/>
<xs:attribute name="contentType"type="xs:string"/>
<xs:attribute name="par"type="xs:string"/>
<xs:anyAttribute namespace="##other"processContents="lax"/>
</xs:complexType>

Representation can be described by the Representation element. The AdaptationSet element may include one or more Representation elements.

The representation may be one of alternative choices of a complete set or subset of media content components that make up the media content for a defined period.

The representation may start at the beginning of the PeriodStart of the period, and may continue to the end of the period. The end of the cycle may be the start of the next cycle or the end of the media presentation.

Each representation can include one or more media streams. Each media stream can be an encoded version of the media content component.

The representation may include one or more segments.

The semantics of the Representation element are described below.

1) Representation element can have the following attributes.'

-The id attribute can specify the identifier of the representation. The id attribute may be unique within the scope of the cycle, unless the representation is functionally identical to other representations within the same cycle. The id attribute may not include whitespace characters.

-The bandwidth attribute can specify the boundary of the data rate and data rate variance of the representation.

The qualityRanking attribute may specify the quality ranking of the representation, relative to other representations in the same adaptation set.

-The dependencyID attribute may specify all complementary representations that depend on the decoding and/or presentation process. The dependencyID attribute may be a space-separated list of values of id attributes.

2) The Representation element can have the following elements.

-The BaseURL element may have an index of 0 to N, and may be used for reference solutions and alternative URL selection.

-The SubRepresentation element may have an index of 0 to N, and may specify information about sub-representation embedded in the representation. It can be used for reference solutions and alternative URL selection.

Table 7 below may represent XML syntax of the AdaptationSet element according to an example.

<!-- Representation -->
<xs:complexType name="RepresentationType">
<xs:complexContent>
<xs:extension base="RepresentationBaseType">
<xs:sequence>
<xs:element name="BaseURL"type="BaseURLType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="SubRepresentation"type="SubRepresentationType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="SegmentBase"type="SegmentBaseType"minOccurs="0"/>
<xs:element name="SegmentList"type="SegmentListType"minOccurs="0"/>
<xs:element name="SegmentTemplate"type="SegmentTemplateType"minOccurs="0"/>
</xs:sequence>
<xs:attribute name="id"type="xs:string"use="required"/>
<xs:attribute name="bandwidth"type="xs:unsignedInt"use="required"/>
<xs:attribute name="qualityRanking"type="xs:unsignedInt"/>
<xs:attribute name="dependencyId"type="StringVectorType"/>
<xs:attribute name="mediaStreamStructureId"type="StringVectorType"/>
</xs:extension></xs:complexContent>
</xs:complexType>

<!-- Whitespace-separated list of strings -->
<xs:simpleType name="StringVectorType">
<xs:list itemType="xs:string"/>
</xs:simpleType>

The sub-representation can be embedded in a regular representation and can be described by the SubRepresentation element. The Representation element may include a SubRepresentation element. The SubRepresentation element may describe properties of one or more media content components embedded in the representation. Representation and sub-representation can share common attributes and elements.

The semantics of the SubRepresentation element are described below.

The SubRepresentation element can have the following attributes.

-The level attribute may specify the level of sub-representation.

-The dependency attribute can specify a set of sub-representations in the presentation that the sub-representation depends on in the decoding and presentation process as a space-separated list of values of the level attribute.

-The bandwidth attribute is the same as the bandwidth attribute of the representation, but can be applied to sub-representation.

-The contentComponet attribute may specify a set of all media content components included in the sub-representation as a space-separated list of values of the id attribute of the ContentComponent element.

Table 8 below may represent XML syntax of a SubRepresentation element according to an example.

<!-- SubRepresentation -->
<xs:complexType name="SubRepresentationType">
<xs:complexContent>
<xs:extension base="RepresentationBaseType">
<xs:attribute name="level"type="xs:unsignedInt"/>
<xs:attribute name="dependencyLevel"type="UIntVectorType"/>
<xs:attribute name="bandwidth"type="xs:unsignedInt"/>
<xs:attribute name="contentComponent"type="StringVectorType"/>
</xs:extension>
</xs:complexContent>
</xs:complexType>

<!-- Whitespace-separated list of unsigned integers -->
<xs:simpleType name="UIntVectorType">
<xs:list itemType="xs:unsignedInt"/>
</xs:simpleType>

Common attributes and elements of the AdaptationSet element, Representation element and SubRepresentation element are described below.

1) AdaptationSet element, Representation element and SubRepresentation element can have the following properties in common.

-The profile attribute may specify a profile between associated presentation(s) according to the media presentation profiles. The value of the profile attribute may be a subset of any higher level value of the document layer (representation, adaptation set and MPD). If the profile attribute is absent, the value of the profile attribute can be considered to be the same as the value of the next higher level in the document hierarchy. For example, if the profile attribute for the representation is absent, the profile attribute for the adaptation set may be valid for the representation.

-The width attribute may specify the horizontal visual presentation size of the video media type on the grid determined by the sar attribute. If the sar attribute is absent, the width and height can be specified as if the value of the sar attribute is "1:1".

-The height attribute may specify the visual presentation size of the video media type on the grid determined by the sar attribute.

The sar attribute may specify a sample length ratio of the video media component type. The sar attribute can take the form of a string containing two integers separated by ":". The first integer may specify a horizontal size based on an arbitrary unit of encoded video pixels. The second integer may specify a vertical size based on an arbitrary unit of encoded video pixels.

The frameRate attribute may specify the output frame rate of the video media type in the representation. If the frame or frame rate fluctuates, the value of the frameRate attribute may be the average frame over the entire duration of the representation or half the average frame rate.

-The audioSampleRate attribute may be a decimal integer value specifying the sampling rate of the audio media component type, and may be a pair of space-separated decimal integer values representing the minimum sampling rate and the maximum sampling rate of the audio media component type, respectively. . The value of the audioSamplingRate attribute may be samples per second.

-The mimeType attribute may specify the MIME type of concatenation of the initial contentization segment.

-The codecs attribute can specify codecs that are played in the representation.

2) The AdaptationSet element, Representation element and SubRepresentation element can have the following elements in common.

-The FramePacking element may have an index of 0 to N, and may specify frame-packing arrangement information of a video media component type.

-The AudioChannelConfiguration element may have an index of 0 to N, and may specify an audio channel configuration of an audio media component type.

-The ContentProtection element may have an index of 0 to N, and specifies information about content protection schemes used for associated presentation.

Table 9 below may represent a common XML syntax of the AdaptationSet element, Representation element, and SubRepresentation element according to an example.

<!-- Representation base (common attributes and elements) -->
<xs:complexType name="RepresentationBaseType">
<xs:sequence>
<xs:element name="FramePacking"type="DescriptorType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="AudioChannelConfiguration"type="DescriptorType"minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="ContentProtection"type="DescriptorType"minOccurs="0"maxOccurs="unbounded"/>
<xs:any namespace="##other"processContents="lax"minOccurs="0"maxOccurs="unbounded"/>
</xs:sequence>
<xs:attribute name="profiles"type="xs:string"/>
<xs:attribute name="width"type="xs:unsignedInt"/>
<xs:attribute name="height"type="xs:unsignedInt"/>
<xs:attribute name="sar"type="xs:string"/>
<xs:attribute name="frameRate"type="xs:string"/>
<xs:attribute name="audioSamplingRate"type="xs:string"/>
<xs:attribute name="mimeType"type="xs:string"/>
<xs:attribute name="segmentProfiles"type="xs:string"/>
<xs:attribute name="codecs"type="xs:string"/>
<xs:attribute name="maximumSAPPeriod"type="xs:double"/>
<xs:attribute name="startWithSAP"type="SAPType"/>
<xs:attribute name="maxPlayoutRate"type="xs:double"/>
<xs:attribute name="codingDependency"type="xs:boolean"/>
<xs:attribute name="scanType"type="VideoScanType"/>
<xs:anyAttribute namespace="##other"processContents="lax"/>
</xs:complexType>
<!-- Stream Access Point type enumeration -->
<xs:simpleType name="SAPType">
<xs:restriction base="xs:unsignedInt">
<xs:minInclusive value="0"/>
<xs:maxInclusive value="6"/>
</xs:restriction>
</xs:simpleType>

<!-- Video Scan type enumeration -->
<xs:simpleType name="VideoScanType">
<xs:restriction base="xs:string">
<xs:enumeration value="progressive"/>
<xs:enumeration value="interlaced"/>
<xs:enumeration value="unknown"/>
</xs:restriction>
</xs:simpleType>

A segment can be the smallest addressable unit described by the MPD with a defined format.

The segment can be referenced by the HTTP-URL included in the MPD. Here, the HTTP-URL may be defined as <absolute-URI> according to RFC 3986. The HTTP-URL can have a fixed scheme "http://" or "https://", and can be limited by the byte range if a range attribute is provided in the URL. The byte range can be expressed as a byte-range-spec defined in RFC 2616. The byte range can be limited to a single expression that identifies the continuous range of bytes.

The representation may be assigned segment information through the presence of the BaseURL element, SegmentBase element, SegmentTemplate element and/or SegmentList element. The segment information may provide information about the location, availability, and properties of all one or more segments included in the representation. In particular, the initial content setting, media, index and existence and location of bitstream switching segments can be provided.

The SegmentBase element, SegmentTemplate element and SegmentList element may be present in the Representation element. Also, the SegmentBase element, the SegmentTemplate element, and the SegmentList element may be present in the Period element or AdaptationSet element to indicate default values. If a SegmentTemplate element or a SegmentList element exists at one level of the hierarchy, it may not be performed at a lower hierarchy level. The SegmentBase element, SegmentTemplate element, and SegmentList element may inherit attributes and elements of the same element at a higher level. If the same attribute or element exists in both levels, a lower level attribute or element may have precedence over a higher level attribute or element.

The SegmentBase element may include sufficient information when a single media segment is provided per presentation and a media segment URL is included in the BaseURL element. When multiple media segments are played, a SegmentList element or a Segment Template element sharing multi-segment base information may be used.

If the representation includes one or more media segments, a duration attribute or SegmentTimeLine element may be played.

The segment list can be defined by one or more SegmentList elements. Each SegmentList element may include a list of SegmentURL elements for a concatenated list of segment URLs. Each segment URL may include a media segment URL, and may include a byte range. The segment URL element may include an index segment.

The segment template can be defined by the SegmentTemplate element. Certain identifiers can be halted to segments to be replaced by dynamic values to create a list of segments.

Segment information can provide the following information.

-Presence content setting, presence or absence of index and bitstream switching segment information.

-HTTP-URL and byte range of each accessible segment within each representation.

-All valid segment URLs declared in MPD.

-Segment availability start time and segment availability end time of each cycle for services whose type attribute of MPD is "dynamic".

-Approximate media presentation start time of each media segment in the media presentation timeline in the cycle.

The segment element or a sub-element of the segment element may include the following attributes.

The duration element may indicate a constant approximate segment duration. All segments in the Representation element can have the same duration. However, the last segment in the cycle may have a different duration.

-The sourceURL attribute can specify a part of the source URL. The sourceURL can have the format <absolute-URI> according to RFC 3986. The sourceURL can have a fixed scheme of "relative-ref" according to "http://", "https://" or RFC 3986. If the sourceURL attribute does not exist, any BaseURL element may be mapped to the sourceURL attribute. Also, a range attribute may be provided if the sourceURL attribute does not exist.

-The range attribute can specify the restriction of the HTTP-URL byte range. The byte range can be expressed and formatted according to the byte-range-spec defined in RFC 2616. If the range attribute is absent, the element may refer to the entire resource referenced in the sourceURL attribute.

Table 10 below shows an XML syntax for information related to a segment in one example.

<!-- Segment information base -->
<xs:complexType name="SegmentBaseType">
<xs:sequence>
<xs:element name="Initialisation"type="URLType"minOccurs="0"/>
<xs:element name="RepresentationIndex"type="URLType"minOccurs="0"/>
<xs:any namespace="##other"processContents="lax"minOccurs="0"maxOccurs="unbounded"/>
</xs:sequence>
<xs:attribute name="timescale"type="xs:unsignedInt"/>
<xs:attribute name="presentationTimeOffset"type="xs:unsignedInt"/>
<xs:attribute name="indexRange"type="xs:string"/>
<xs:attribute name="indexRangeExact"type="xs:boolean"/>
<xs:anyAttribute namespace="##other"processContents="lax"/>
</xs:complexType>

<!-- Multiple Segment information base -->
<xs:complexType name="MultipleSegmentBaseType">
<xs:complexContent>
<xs:extension base="SegmentBaseType">
<xs:sequence>
<xs:element name="SegmentTimeline"type="SegmentTimelineType"minOccurs="0"/>
<xs:element name="BitstreamSwitching"type="URLType"minOccurs="0"/>
</xs:sequence>
<xs:attribute name="duration"type="xs:unsignedInt"/>
<xs:attribute name="startNumber"type="xs:unsignedInt"/>
</xs:extension>
</xs:complexContent>
</xs:complexType>

<!-- Segment Info item URL/range -->
<xs:complexType name="URLType">
<xs:sequence>
<xs:any namespace="##other"processContents="lax"minOccurs="0"maxOccurs="unbounded"/>
</xs:sequence>
<xs:attribute name="sourceURL"type="xs:anyURI"/>
<xs:attribute name="range"type="xs:string"/>
<xs:anyAttribute namespace="##other"processContents="lax"/>
</xs:complexType><xs:enumerationvalue="progressive"/>
<xs:enumeration value="interlaced"/>
<xs:enumeration value="unknown"/>
</xs:restriction>
</xs:simpleType>

In the following, an additional configuration for selecting a representation based on user and terminal characteristics is described.

According to the solution described above for DASH, representations can be described by various metadata. Most of the characteristics of the representation may be for selecting representations based on the characteristics of the terminal. For example, characteristics of the terminal may include resolution and connection bandwidth.

The accessibility characteristics of the representation can be used to support disabled users who suffer difficulties in perceiving multimedia content. The following embodiments to support accessibility are 1) MPEG-21 Digital Item Adaptation (DIA) accessibility description and 2) content components to enable enhancement/replacement. (facilitate) Can contain some hints. In essence, the MPEG-21 DIA accessibility description, which includes elements of VisualImpairmentType (visual impairment type) and/or AuditoryImpairmentType (auditory impairment type) of ISO/IEC 21000-7, can be used for a variety of visual or auditory impairments of the user. It makes it possible to explain the symptoms. The user's visual or audible disability may include color deficiency or low vision.

The following rules can be applied to URIs to identify specific accessibility schemes. For example, schemes can be included in the Accessibility element described above.

URIs for representations including video and/or audio content may be defined as shown in Table 11 below.

urn:mpeg:mpegB;dash:dash:mp21accessibility:<value>

The above URI may indicate accessibility schemes based on the accessibility definition of ISO/IEC 21000-7.

If <value> is "s0", a suitable representation is prepared in advance, and the associated accessibility description can be described by the Accessibility element. Different ways can be used to convey the above description. For example, the accessibility description can be carried by the MP21Access element, and can be referenced by the xlink:href attribute defined below.

If <value> is "s1", the provider can obtain the accessibility description of the disabled user in any way, and provide appropriate content to the disabled user.

In the context of DASH, if a representation is associated with accessibility information, the representation can be used for the person with a disability whose specific symptoms are described by the accessibility description. In general, the media of the above representation can be augmented to cope with the handicapped person's problem. Here, the enhancement of the representation may be contrast or adjustment of color.

The above-mentioned Accessibility element can be extended as follows. The new child element "MP21Access" can be used as a container for describing MPEG-21 DIA accessibility. In addition, an additional xlink:href attribute may be added to the Accessibility element to refer to an external description including MPEG-21 DIA accessibility elements.

Furthermore, a new attribute "use" can be employed as a hint to inform the client of the intended use of the representation for the purpose of accessibility. These new elements and attributes can be applied to the representation group (or adaptation set), representation and subrepresentation.

The semantics of elements and attributes to support accessibility are described below.

1) Group element, Adaptation Set element, Representation element or SubRepresentation element may further have the following properties to support accessibility.

-The use attribute may indicate the intended use of the representation(s). The value of the use attribute may be signLang, subtitle, caption, description or plusDes. signLang can be used as sign language. A subtitle can be used as a subtitle. Caption can indicate use as a caption. The caption can be a subtitle with additional description. The description may indicate use as a description, such as an audio description of a movie. plusDesc may indicate that the content of the corresponding representation has been increased by including descriptions. For example, it may point to an augmented soundtrack including audio descriptions.

-The xlink:href attribute may provide a reference to an external MPEG-21 DIA including the AuditoryImpairmentType and/or VisualImpairmentType elements of the ISO/IEC IS 21000-7 element. The representation or group of representations associated with the above description may be suitable for persons with disabilities having the problems described by the above description.

-The xlink:actuate attribute can provide processing instructions. The processing instructions can be "onLoad" or "onRequest". The xlink:actuate attribute cannot exist if the xlink:href attribute is absent.

2) Group element, Adaptation Set element, Representation element or SubRepresentation element may further have the following elements to support accessibility.

-The Accessibility element may have an index of 0 to N, and may provide information about an accessibility information scheme.

-The MP21Access element may have an index of 0 to 1, and may include an MPEG-21 DIA description with ISO/IEC 21000-7 AuditoryImpairmentType and/or VisualImpairmentType elements. The representations or group of representations associated with the above description may be suitable for persons with disabilities having the problems described by the above description.

Table 12 below may represent an XML syntax for supporting accessibility of a Group element, an Adaptation Set element, a Representation element, or a SubRepresentation element according to an example.

<!-- RepresentationBase type; extended by other Representation-related types -->
<xs:complexType name="RepresentationBaseType">
<xs:sequence>
<xs:element name="ContentProtection"type="ContentDescriptorType"
minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Accessibility"type="ContentDescriptorType"
minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Rating"type="ContentDescriptorType"
minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Viewpoint"type="ContentDescriptorType"
minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="MultipleViews"type="MultipleViewsType"minOccurs="0"/>
<xs:any namespace="##other"processContents="lax"minOccurs="0"maxOccurs="unbounded"/>
</xs:sequence>
<xs:attribute name="group"type="xs:unsignedInt"/>
<xs:attribute name="width"type="xs:unsignedInt"/>
<xs:attribute name="height"type="xs:unsignedInt"/>
<xs:attribute name="parx"type="xs:unsignedInt"/>
<xs:attribute name="pary"type="xs:unsignedInt"/>
<xs:attribute name="lang"type="LangVectorType"/>
<xs:attribute name="mimeType"type="xs:string"/>
<xs:attribute name="startWithRAP"type="xs:boolean"/>
<xs:attribute name="frameRate"type="xs:double"/>
<xs:attribute name="maximumRAPPeriod"type="xs:double"/>
<xs:attribute name="numberOfChannels"type="StringVectorType"/>
<xs:attribute name="samplingRate"type="StringVectorType"/>
<xs:attribute name="use"type="UseType"/>
<xs:anyAttribute namespace="##other"processContents="lax"/>
</xs:complexType>

<xs:simpleType name="UseType">
<xs:restriction base="xs:string">
<xs:enumeration value="signLang"/>
<xs:enumeration value="subtitle"/>
<xs:enumeration value="caption"/>
<xs:enumeration value="description"/>
<xs:enumeration value="plusDesc"/>
</xs:restriction>
</xs:simpleType>

<!-- Generic named descriptive information about the content -->
<xs:complexType name="ContentDescriptorType">
<xs:sequence>
<xs:element minOccurs="0"name="SchemeInformation"type="xs:string"/>
<xs:element minOccurs="0"name="MP21Access"type="xs:string"/>
<xs:any namespace="##other"processContents="lax"minOccurs="0"maxOccurs="unbounded"/>
</xs:sequence>
<xs:attribute name="schemeIdUri"type="xs:anyURI"use="required"/>
<xs:attribute ref="xlink:href"/>
<xs:attribute ref="xlink:actuate"default="onRequest"/>
<xs:anyAttribute namespace="##other"processContents="lax"/>
</xs:complexType>

In the following, metadata describing the relationship between representations is described.

Metadata describing the relationship between representation groups is relatively rare. For example, it is difficult to tell the client which video stream a given audio description is associated with. In some cases, two representation groups may be semantically equivalent, and only one representation group may need to be selected according to the context. In the following, two simple attributes are proposed for the purpose described above. The metadata described below may be useful for accessibility as well as general adaptability.

The Group element, the Adaptation Set element, the Representation element, or the SubRepresentation element may further have the following attributes to describe the relationship between representations.

-The usedWith attribute may point to a list of one or more representations or groups of representations. If the current representation or group of representations is used, the usedWith attribute can be used with any item in the list above. For example, a representation group for audio description can be used with a specific representation group of video components. The value of the usedWith attribute may be a whitespace-separated list. Each item in the space-separated list can be one representation group or an identification of one representation. The identification of the representation group may be a value of a group attribute or an adaptationSet attribute. The identification of the representation may have a format of the repid attribute. The repid attribute may be the value of the id attribute of the representation.

-The equivalentTo attribute may point to a list of one or more representations or groups of representations. The current representation can be used instead of any item in the list above. For example, a representation group for subtitles may be used instead of a specific representation group of audio components. The format of the equivalentTo attribute can be the same as that of the usedWith attribute.

Table 13 below may represent an XML syntax for describing a relationship between representations of a Group element, an Adaptation Set element, a Representation element, or a SubRepresentation element according to an example.

<!-- RepresentationBase type; extended by other Representation-related types -->
<xs:complexType name="RepresentationBaseType">
<xs:sequence>
<xs:element name="ContentProtection"type="ContentDescriptorType"
minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Accessibility"type="ContentDescriptorType"
minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Rating"type="ContentDescriptorType"
minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Viewpoint"type="ContentDescriptorType"
minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="MultipleViews"type="MultipleViewsType"minOccurs="0"/>
<xs:any namespace="##other"processContents="lax"minOccurs="0"maxOccurs="unbounded"/>
</xs:sequence>
<xs:attribute name="group"type="xs:unsignedInt"/>
<xs:attribute name="width"type="xs:unsignedInt"/>
<xs:attribute name="height"type="xs:unsignedInt"/>
<xs:attribute name="parx"type="xs:unsignedInt"/>
<xs:attribute name="pary"type="xs:unsignedInt"/>
<xs:attribute name="lang"type="LangVectorType"/>
<xs:attribute name="mimeType"type="xs:string"/>
<xs:attribute name="startWithRAP"type="xs:boolean"/>
<xs:attribute name="frameRate"type="xs:double"/>
<xs:attribute name="maximumRAPPeriod"type="xs:double"/>
<xs:attribute name="numberOfChannels"type="StringVectorType"/>
<xs:attribute name="samplingRate"type="StringVectorType"/>
<xs:attribute name="usedWith"type="StringVectorType"/>
<xs:attribute name="equivalentTo"type="StringVectorType"/>
<xs:anyAttribute namespace="##other"processContents="lax"/>
</xs:complexType>

<!-- Type for space delimited list of strings -->
<xs:simpleType name="StringVectorType">
<xs:list itemType="xs:string"/>
</xs:simpleType>

In the following, metadata for bit depth is described.

To select different representations for terminals with different display bit depths, the following properties can be used for the representation and the representation group. The bit depth may refer to the number of bits used to represent a luma/chroma sample of visual content.

The semantics of the attributes for bit depth are described below.

The Group element, the Adaptation Set element, the Representation element, or the SubRepresentation element may further have the following attributes to provide bit depth.

-The bitDepth attribute may indicate the number of bits for representing a luma/chroma sample of visual content. If, for example, in different video pictures, the bit depth fluctuates, the value of the bitDepth attribute may be the maximum value of the bit depths.

Table 14 below may represent an XML syntax for supporting a bit depth of a Group element, an Adaptation Set element, a Representation element, or a SubRepresentation element according to an example.

<!-- RepresentationBase type; extended by other Representation-related types -->
<xs:complexType name="RepresentationBaseType">
<xs:sequence>
<xs:element name="ContentProtection"type="ContentDescriptorType"
minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Accessibility"type="ContentDescriptorType"
minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Rating"type="ContentDescriptorType"
minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="Viewpoint"type="ContentDescriptorType"
minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="MultipleViews"type="MultipleViewsType"minOccurs="0"/>
<xs:any namespace="##other"processContents="lax"minOccurs="0"maxOccurs="unbounded"/>
</xs:sequence>
<xs:attribute name="group"type="xs:unsignedInt"/>
<xs:attribute name="width"type="xs:unsignedInt"/>
<xs:attribute name="height"type="xs:unsignedInt"/>
<xs:attribute name="parx"type="xs:unsignedInt"/>
<xs:attribute name="pary"type="xs:unsignedInt"/>
<xs:attribute name="lang"type="LangVectorType"/>
<xs:attribute name="mimeType"type="xs:string"/>
<xs:attribute name="startWithRAP"type="xs:boolean"/>
<xs:attribute name="frameRate"type="xs:double"/>
<xs:attribute name="maximumRAPPeriod"type="xs:double"/>
<xs:attribute name="numberOfChannels"type="StringVectorType"/>
<xs:attribute name="samplingRate"type="StringVectorType"/>
<xs:attribute name="use"type="UseType"/>
<xs:anyAttribute namespace="##other"processContents="lax"/>
</xs:complexType>

<xs:simpleType name="UseType">
<xs:restriction base="xs:string">
<xs:enumeration value="signLang"/>
<xs:enumeration value="subtitle"/>
<xs:enumeration value="caption"/>
<xs:enumeration value="description"/>
<xs:enumeration value="plusDesc"/>
</xs:restriction>
</xs:simpleType>

<!-- Generic named descriptive information about the content -->
<xs:complexType name="ContentDescriptorType">
<xs:sequence>
<xs:element minOccurs="0"name="SchemeInformation"type="xs:string"/>
<xs:element minOccurs="0"name="MP21Access"type="xs:string"/>
<xs:any namespace="##other"processContents="lax"minOccurs="0"maxOccurs="unbounded"/>
</xs:sequence>
<xs:attribute name="schemeIdUri"type="xs:anyURI"use="required"/>
<xs:attribute ref="xlink:href"/>
<xs:attribute ref="xlink:actuate"default="onRequest"/>
<xs:anyAttribute namespace="##other"processContents="lax"/>
</xs:complexType>

To correspond to the above description, two attributes minBitDepth and maxBitDepth can be added to the Representation Group element or the Adaptation Set element.

In the following, semantics of the attributes describing the maximum bit depth and minimum bit depth are described.

The Representation Group element, Group element or Adaptation Set element may further have the following attributes to describe the maximum bit depth and the minimum bit depth.

-The xlink:href attribute can indicate a reference to an external Group element or an Adaptation Set element.

-The xlink:actuate attribute can provide processing instructions. The processing instructions can be "onLoad" or "onRequest".

The minBitDepth attribute may indicate a minimum bit depth value for all representations in a group or adaptation set.

The maxBitDepth attribute may indicate the maximum bit depth value for all representations in a group or adaptation set.

Table 15 below may represent XML syntax for supporting a minimum bit depth value and a maximum bit depth value of a Representation Group element, a Group element, or an Adaptation Set element according to an example.

<!-- Group to contain information common to a group;
extends RepresentationBaseType -->
<xs:complexType name="GroupType">
<xs:complexContent>
<xs:extension base="RepresentationBaseType">
<xs:sequence>
<xs:element name="Representation"type="RepresentationType"
minOccurs="0"maxOccurs="unbounded"/>
<xs:element name="SegmentInfoDefault"type="SegmentInfoDefaultType"minOccurs="0"/>
</xs:sequence>
<xs:attribute ref="xlink:href"/>
<xs:attribute ref="xlink:actuate"default="onRequest"/>
<xs:attribute name="minBandwidth"type="xs:unsignedInt"/>
<xs:attribute name="maxBandwidth"type="xs:unsignedInt"/>
<xs:attribute name="minWidth"type="xs:unsignedInt"/>
<xs:attribute name="maxWidth"type="xs:unsignedInt"/>
<xs:attribute name="minHeight"type="xs:unsignedInt"/>
<xs:attribute name="maxHeight"type="xs:unsignedInt"/>
<xs:attribute name="minFrameRate"type="xs:double"/>
<xs:attribute name="maxFrameRate"type="xs:double"/>
<xs:attribute name="minBitDepth"type="xs:unsignedInt"/>
<xs:attribute name="maxBitDepth"type="xs:unsignedInt"/>
<xs:attribute name="subsegmentAlignment"type="xs:boolean"default="false"/>
<xs:attribute name="segmentAlignmentFlag"type="xs:boolean"/>
<xs:attribute name="bitStreamSwitchingFlag"type="xs:boolean"/>
<xs:anyAttribute namespace="##other"processContents="lax"/>
</xs:extension>
</xs:complexContent>
</xs:complexType>

2 is a signal flow diagram of a content processing method according to an embodiment of the present invention.

The terminal 200 may be a client of DASH described above.

DASH's clients are compatible with the clients specified in RFC 2616.

DASH's client can use the HTTP GET method or HTTP partial GET method, as specified in RFC 2616, to access segments or portions of segments.

Server 210 may host segments of DASH. The server 210 may be compatible with the server specified in RFC 2616.

In step 220, the terminal 200 may receive metadata of the media content from the server 210. That is, the server 210 transmits metadata about the media content to the terminal 200. The media content may include one or more cycles.

Metadata may be MPD.

The MPD may provide sufficient information to provide a streaming service to the user by accessing the segments through the protocol specified in the scheme of resources defined by the terminal 200. Here, the specified protocol may be HTTP/1.1. The server 210 may provide an MPD delivery function. MPD may be generated according to DASH media presentation preparation.

In step 230, the terminal 200 may process the received metadata. In step 230, the terminal 200 may extract information provided by the metadata or information included in the metadata.

In steps 240 to 250, the terminal 200 may access a segment of media content based on information provided by metadata. The server 210 may be an HTTP server that provides a DASH segment delivery function.

Here, each period may include one or more groups, and each group may include one or more representations of media content. That is, each cycle may include one or more representations of media content. Accordingly, each representation may start at the start point of the cycle including itself and continue to the end point of the cycle. Each representation may include one or more segments.

In step 240, the terminal 200 may request a segment of media content from the server 210 using the segment URL. Here, the URL may be interpreted in relation to the base URL element described above. For example, the URL of the segment can be generated based on the base URL element.

The MPD provides sufficient information to the terminal 200 to provide a streaming service to the user by 1) requesting the segments to the server 210 and 2) demultiplexing, decoding and rendering the media streams included in the segment. can do.

The terminal 200 may request the server 210 a suitable segment for a specific period based on the metadata processing. That is, the requested segment may be selected based on metadata. The terminal 200 may request the segment 210 from the server 210 by executing an HTTP GET method.

Metadata may include scope attributes. The request may be a request for bytes designated by a range attribute of a resource indicated by the URL.

The URL of the segment can be an absolute URL or a relative URL.

The terminal 200 may select a period, an adaptation set and a representation, etc. using an element or attribute included in the metadata, and a segment to request based on the selected period, the adaptation set, or the element and attribute of the representation You can choose

For example, for one or more representations included in the cycle, each representation may include information to assist people with disabilities who are having difficulty in perceiving media content. The media component of the representation can be augmented to deal with the handicapped person's problem. The enhancement may be one or more of an enhancement of contrast and an enhancement of color correction. In addition, the above information may indicate the intended use of the representation. Here, the intended use may be one or more of sign language, subtitles, captions, and descriptions. In addition, the above information may include an attribute that provides a reference to an external MPEG-21 Digital Item Adaptation (DIA).

For example, metadata may include attributes that describe the relationship between one or more representations. The first representation of the one or more representations may include an attribute pointing to a list of representations of some of the one or more representations, and the first representation of the some representations Can be used with one. Here, the first representation may be a representation for audio description, and some representations may be representations of video components, respectively. In addition, the second representation of the one or more representations may include an attribute indicating a list of representations of some of the one or more representations above, and one of the representations of some of the above The representation of can be used in place of the second representation.

For example, for one or more representations included in the period, each representation may include a bit depth attribute used to select a different representation for terminals with different display bit depths.

The bit depth attribute may indicate the number of bits for representing a luma/chroma sample of visual content.

In step 245, in some cases, the server 210 needs to parse the media content (eg, MP4 file for SVC), and can extract data parts suitable for the requested segment. .

In step 250, the server 210 may transmit suitable segments for each request from the terminal 200 to the terminal 200. The terminal 200 may receive segments from the server 210.

In step 260, the terminal 200 may play media by decoding and rendering data of media included in the segment.

The terminal 200 may play media using the received segment by repeating steps 220 to 260.

Technical contents according to an embodiment of the present invention described above with reference to FIG. 1 may be applied to the present embodiment as it is. Therefore, a more detailed description will be omitted below.

3 illustrates categories of signaling information according to an example of the present invention.

Signaling information (ie, metadata) may be divided into the following categories 1) to 4).

1) General information 310: General information may include a general description of content and a general description of each interval, such as, for example, duration and start time.

2) Quality of service information (QoS information) 320: It may describe characteristics of each alternative, such as bitrate, resolution, and quality. That is, the quality information of the service can describe the characteristics of each of the alternatives of the content.

The alternatives can be physical (ie, pre-generated) and virtual (ie, created on-the-fly). Based on the information of the alternatives, the client can select a suitable alternative fragment. Accordingly, it is possible to support aptivity to contexts of terminals and networks.

3) Mapping Information (330): It is possible to describe locations to extract content. Depending on the specific cases, different alternatives can have the same or different locations.

4) Client request 340: This kind of signaling information may conform to the format of an HTTP 1.1 request message. The parameters requested by the client may be derived from the information of the categories 1) to 3) above.

FIG. 4 shows the level of content division layer and signaling information according to an example of the present invention.

The signaling of metadata according to the date and time of the present invention may be physically separated into content-level information 410, interval level information 420, QoS information 430, and mapping 440 information. Linking of related parts of the content-level information 310, interval level information 420, QoS information 430, and mapping 440 may be performed by referencing.

These parts of the signaling information can be combined in different ways to support flexibility.

For example, when only content-level information 410 and interval level information 420 are transmitted to the client, calculations for determination of all alternatives and resolution of locations can be performed by the server. Therefore, the processing model when only the content-level information 310 and the interval level information 420 are transmitted to the client may be “server-based”.

If content-level information 410, interval-level information 420 and QoS information 430 are transmitted to the client, calculations for determination of all alternatives and resolution of locations are distributed by the client and server Can be performed. Thus, when the content-level information 410, interval-level information 420 and QoS information 430 are transmitted to the client, the above model may be "distributed".

When all signaling information (content-level information 410, interval-level information 320, QoS information 430 and mapping information 440) is transmitted to the client, most (or all) of these models Since processing (i.e., computation for determination of alternatives and resolution of locations) is performed at the client, the model may be client-based.

Separation of metadata parts can enable efficiency in storage and delivery. For example, during the session, metadata of the content-level information 410 can be sent once, and only the interval level information 420 can be periodically updated. Similarly, one file containing QoSInfo part 430 can be used for different intervals and different content.

5 is a structural diagram of a terminal according to an embodiment of the present invention.

The structure of the terminal 100 to be described below may represent logical components of the conceptual DASH client model.

The terminal 100 may include an access engine 510 and a media engine 520.

The access engine 510 may be a DASH access engine.

The access engine 510 may receive metadata (eg, MPD) from the server 110.

The access engine 510 may configure requests, and issue the configured requests to the server 110.

The access engine 510 may receive content (eg, aender, segments or portions of segments) from the server 110.

The access engine 510 may provide content to the media engine 520.

The output of the access engine 510 is a media (or media) of an MPEG container (eg, ISO/IEC 14492-12 ISO base media file format or ISO/IEC 13818-2 MPEG-2 transport stream). Part of). In addition, the output of the access engine 510 may include timing information that maps the internal timing of the media to the timeline of the media presentation.

In addition, the access engine 510 may perform functions described as performed by the terminal 200 in steps 220 to 260 described above with reference to FIG. 2.

The media engine 520 can play the provided content. That is, the media engine 520 may output media using the media and timing information output from the access engine 510.

Technical contents according to an embodiment of the present invention described above with reference to FIGS. 1 to 4 may be applied to the present embodiment as it is. Therefore, a more detailed description will be omitted below.

The method according to an embodiment of the present invention may be implemented in the form of program instructions that can be executed through various computer means and recorded in a computer readable medium. The computer-readable medium may include program instructions, data files, data structures, or the like alone or in combination. The program instructions recorded on the medium may be specially designed and configured for the present invention, or may be known and available to those skilled in computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs, DVDs, and magnetic media such as floptical disks. -Hardware devices specifically configured to store and execute program instructions such as magneto-optical media, and ROM, RAM, flash memory, and the like. Examples of program instructions include high-level language codes that can be executed by a computer using an interpreter, etc., as well as machine language codes produced by a compiler. The hardware device described above may be configured to operate as one or more software modules to perform the operation of the present invention, and vice versa.

As described above, although the present invention has been described with limited embodiments and drawings, the present invention is not limited to the above embodiments, and various modifications and variations from these descriptions will be made by those of ordinary skill in the art to which this invention belongs This is possible.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the following claims, but also by the claims and equivalents.

200: terminal
210: server

Claims (27)

delete delete delete In the media content providing method performed by the client,
Receiving at least one media presentation description (MPD) of the media content; And
Accessing a segment of the media content, based on the information provided by the MPD
Including,
The MPD includes one or a plurality of periods,
Each of the periods includes one or a plurality of adaptation sets,
Each of the adaptation sets includes one or a plurality of representations,
Each of the representations includes one or a plurality of segments,
The MPD, period, adaptation set, representation, or segment includes one or a plurality of attributes or elements,
The adaptation set,
A method for providing media content including one or a plurality of attributes or elements common to each of the representations of the adaptation set. The method of claim 4,
The MPD is a method for providing media content including sampling rate information or channel information of the media content. The method of claim 4,
The attribute included in the level of the adaptation set includes at least one of Accessibility, audioSampleRate, AudioChannelConfiguration or contentType,
The Accessibility indicates information about an accessibility scheme,
The audioSampleRate represents a sampling rate of an audio media component type,
The AudioChannelConfiguration represents an audio channel configuration of an audio media component type,
The contentType is a media content providing method indicating the type of the media content component. The method of claim 4,
The MPD,
A method for providing media content including a sample aspect ratio of a video media component type. The method of claim 4,
The attribute included in the level of the MPD is suggestedPresentationDelay or maxSegmentDuration,
The maxSegmentDuration is,
A method for providing media content that is the maximum duration of a segment in a presentation. The method of claim 4,
The attribute included in the level of the adaptation set is subsegmentStartsWithSAP. The method of claim 4,
The MPD, the media content providing method comprising at least one of SegmentBase, SegmentTemplate or SegmentList. In the method for providing media content performed by one or a plurality of servers,
Transmitting at least one media presentation description (MPD) of the media content to the client;
Receiving a request for a segment of media content from the client;
Transmitting media content to the client
Including,
The MPD includes one or a plurality of periods,
Each of the periods includes one or a plurality of adaptation sets,
Each of the adaptation sets includes one or a plurality of representations,
Each of the representations includes one or a plurality of segments,
The MPD, period, adaptation set, representation, or segment includes one or a plurality of attributes or elements,
The adaptation set,
A method for providing media content including one or a plurality of attributes or elements common to each of the representations of the adaptation set. The method of claim 11,
The MPD is a method for providing media content including sampling rate information or channel information of the media content. The method of claim 11,
The attribute included in the level of the adaptation set includes at least one of Accessibility, audioSampleRate, AudioChannelConfiguration or contentType,
The Accessibility indicates information about an accessibility scheme,
The audioSampleRate represents a sampling rate of an audio media component type,
The AudioChannelConfiguration represents an audio channel configuration of an audio media component type,
The contentType is a media content providing method indicating the type of the media content component. The method of claim 11,
The MPD,
A method for providing media content including a sample aspect ratio of a video media component type. The method of claim 11,
The attribute included in the level of the MPD is suggestedPresentationDelay or maxSegmentDuration,
The maxSegmentDuration is,
Method for providing media content that is a maximum duration of a segment in the representation. The method of claim 11,
The attribute included in the level of the adaptation set is subsegmentStartsWithSAP. The method of claim 11,
The MPD, the media content providing method comprising at least one of SegmentBase, SegmentTemplate or SegmentList. In the method for providing media content performed by one or a plurality of servers,
Transmitting at least one media presentation description (MPD) of the media content to the client;
Receiving a request for a segment of media content from the client;
Transmitting media content to the client
Including,
The MPD includes one or a plurality of periods,
Each of the periods includes one or a plurality of adaptation sets,
Each of the adaptation sets includes one or a plurality of representations,
Each of the representations includes one or a plurality of segments,
A method for providing media content in which information about the location, availability, or properties of one or more segments in the representation is included in the SegmentBase element. In the method for providing media content performed by one or a plurality of servers,
Transmitting at least one media presentation description (MPD) of the media content to the client;
Receiving a request for a segment of media content from the client;
Transmitting media content to the client
Including,
The MPD includes one or a plurality of periods,
Each of the periods includes one or a plurality of adaptation sets,
Each of the adaptation sets includes one or a plurality of representations,
Each of the representations includes one or a plurality of segments,
A method for providing media content in which information about the location, availability, or properties of one or more segments in the representation is included in the SegmentTemplate element. The method of claim 19,
The MPD, a media content providing method including a duration attribute and a SegmentTimeline element. In the method for providing media content performed by one or a plurality of servers,
Transmitting at least one media presentation description (MPD) of the media content to the client;
Receiving a request for a segment of media content from the client;
Transmitting media content to the client
Including,
The MPD includes one or a plurality of periods,
Each of the periods includes one or a plurality of adaptation sets,
Each of the adaptation sets includes one or a plurality of representations,
Each of the representations includes one or a plurality of segments,
A method for providing media content in which information about the location, availability, or properties of one or more segments in the representation is included in the SegmentList element. The method of claim 21,
The MPD, a media content providing method including a duration attribute and a SegmentTimeline element. In the media content providing method performed by the client,
Receiving at least one media presentation description (MPD) of the media content; And
Accessing a segment of the media content, based on the information provided by the MPD
Including,
The MPD includes one or a plurality of periods,
Each of the periods includes one or a plurality of adaptation sets,
Each of the adaptation sets includes one or a plurality of representations,
Each of the representations includes one or a plurality of segments,
A method for providing media content in which information about the location, availability, or properties of one or more segments in the representation is included in the SegmentBase element. In the media content providing method performed by the client,
Receiving at least one media presentation description (MPD) of the media content; And
Accessing a segment of the media content, based on the information provided by the MPD
Including,
The MPD includes one or a plurality of periods,
Each of the periods includes one or a plurality of adaptation sets,
Each of the adaptation sets includes one or a plurality of representations,
Each of the representations includes one or a plurality of segments,
A method for providing media content in which information about the location, availability, or properties of one or more segments in the representation is included in the SegmentTemplate element. The method of claim 24,
The MPD, a media content providing method including a duration attribute and a SegmentTimeline element. In the media content providing method performed by the client,
Receiving at least one media presentation description (MPD) of the media content; And
Accessing a segment of the media content, based on the information provided by the MPD
Including,
The MPD includes one or a plurality of periods,
Each of the periods includes one or a plurality of adaptation sets,
Each of the adaptation sets includes one or a plurality of representations,
Each of the representations includes one or a plurality of segments,
A method for providing media content in which information about the location, availability, or properties of one or more segments in the representation is included in the SegmentList element. The method of claim 26,
The MPD, a media content providing method including a duration attribute and a SegmentTimeline element.

Images